xref: /linux/drivers/gpio/gpio-mpc8xxx.c (revision 03f7c1d2a49acd30e38789cd809d3300721e9b0e)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * GPIOs on MPC512x/8349/8572/8610/QorIQ and compatible
4  *
5  * Copyright (C) 2008 Peter Korsgaard <jacmet@sunsite.dk>
6  * Copyright (C) 2016 Freescale Semiconductor Inc.
7  */
8 
9 #include <linux/acpi.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/spinlock.h>
13 #include <linux/io.h>
14 #include <linux/of.h>
15 #include <linux/of_gpio.h>
16 #include <linux/of_address.h>
17 #include <linux/of_irq.h>
18 #include <linux/of_platform.h>
19 #include <linux/property.h>
20 #include <linux/mod_devicetable.h>
21 #include <linux/slab.h>
22 #include <linux/irq.h>
23 #include <linux/gpio/driver.h>
24 #include <linux/bitops.h>
25 #include <linux/interrupt.h>
26 
27 #define MPC8XXX_GPIO_PINS	32
28 
29 #define GPIO_DIR		0x00
30 #define GPIO_ODR		0x04
31 #define GPIO_DAT		0x08
32 #define GPIO_IER		0x0c
33 #define GPIO_IMR		0x10
34 #define GPIO_ICR		0x14
35 #define GPIO_ICR2		0x18
36 #define GPIO_IBE		0x18
37 
38 struct mpc8xxx_gpio_chip {
39 	struct gpio_chip	gc;
40 	void __iomem *regs;
41 	raw_spinlock_t lock;
42 
43 	int (*direction_output)(struct gpio_chip *chip,
44 				unsigned offset, int value);
45 
46 	struct irq_domain *irq;
47 	int irqn;
48 };
49 
50 /*
51  * This hardware has a big endian bit assignment such that GPIO line 0 is
52  * connected to bit 31, line 1 to bit 30 ... line 31 to bit 0.
53  * This inline helper give the right bitmask for a certain line.
54  */
55 static inline u32 mpc_pin2mask(unsigned int offset)
56 {
57 	return BIT(31 - offset);
58 }
59 
60 /* Workaround GPIO 1 errata on MPC8572/MPC8536. The status of GPIOs
61  * defined as output cannot be determined by reading GPDAT register,
62  * so we use shadow data register instead. The status of input pins
63  * is determined by reading GPDAT register.
64  */
65 static int mpc8572_gpio_get(struct gpio_chip *gc, unsigned int gpio)
66 {
67 	u32 val;
68 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
69 	u32 out_mask, out_shadow;
70 
71 	out_mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_DIR);
72 	val = gc->read_reg(mpc8xxx_gc->regs + GPIO_DAT) & ~out_mask;
73 	out_shadow = gc->bgpio_data & out_mask;
74 
75 	return !!((val | out_shadow) & mpc_pin2mask(gpio));
76 }
77 
78 static int mpc5121_gpio_dir_out(struct gpio_chip *gc,
79 				unsigned int gpio, int val)
80 {
81 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
82 	/* GPIO 28..31 are input only on MPC5121 */
83 	if (gpio >= 28)
84 		return -EINVAL;
85 
86 	return mpc8xxx_gc->direction_output(gc, gpio, val);
87 }
88 
89 static int mpc5125_gpio_dir_out(struct gpio_chip *gc,
90 				unsigned int gpio, int val)
91 {
92 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
93 	/* GPIO 0..3 are input only on MPC5125 */
94 	if (gpio <= 3)
95 		return -EINVAL;
96 
97 	return mpc8xxx_gc->direction_output(gc, gpio, val);
98 }
99 
100 static int mpc8xxx_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
101 {
102 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
103 
104 	if (mpc8xxx_gc->irq && offset < MPC8XXX_GPIO_PINS)
105 		return irq_create_mapping(mpc8xxx_gc->irq, offset);
106 	else
107 		return -ENXIO;
108 }
109 
110 static irqreturn_t mpc8xxx_gpio_irq_cascade(int irq, void *data)
111 {
112 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = data;
113 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
114 	unsigned long mask;
115 	int i;
116 
117 	mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_IER)
118 		& gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR);
119 	for_each_set_bit(i, &mask, 32)
120 		generic_handle_domain_irq(mpc8xxx_gc->irq, 31 - i);
121 
122 	return IRQ_HANDLED;
123 }
124 
125 static void mpc8xxx_irq_unmask(struct irq_data *d)
126 {
127 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
128 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
129 	unsigned long flags;
130 
131 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
132 
133 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR,
134 		gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR)
135 		| mpc_pin2mask(irqd_to_hwirq(d)));
136 
137 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
138 }
139 
140 static void mpc8xxx_irq_mask(struct irq_data *d)
141 {
142 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
143 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
144 	unsigned long flags;
145 
146 	raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
147 
148 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR,
149 		gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR)
150 		& ~mpc_pin2mask(irqd_to_hwirq(d)));
151 
152 	raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
153 }
154 
155 static void mpc8xxx_irq_ack(struct irq_data *d)
156 {
157 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
158 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
159 
160 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IER,
161 		      mpc_pin2mask(irqd_to_hwirq(d)));
162 }
163 
164 static int mpc8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
165 {
166 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
167 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
168 	unsigned long flags;
169 
170 	switch (flow_type) {
171 	case IRQ_TYPE_EDGE_FALLING:
172 	case IRQ_TYPE_LEVEL_LOW:
173 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
174 		gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
175 			gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
176 			| mpc_pin2mask(irqd_to_hwirq(d)));
177 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
178 		break;
179 
180 	case IRQ_TYPE_EDGE_BOTH:
181 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
182 		gc->write_reg(mpc8xxx_gc->regs + GPIO_ICR,
183 			gc->read_reg(mpc8xxx_gc->regs + GPIO_ICR)
184 			& ~mpc_pin2mask(irqd_to_hwirq(d)));
185 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
186 		break;
187 
188 	default:
189 		return -EINVAL;
190 	}
191 
192 	return 0;
193 }
194 
195 static int mpc512x_irq_set_type(struct irq_data *d, unsigned int flow_type)
196 {
197 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_data_get_irq_chip_data(d);
198 	struct gpio_chip *gc = &mpc8xxx_gc->gc;
199 	unsigned long gpio = irqd_to_hwirq(d);
200 	void __iomem *reg;
201 	unsigned int shift;
202 	unsigned long flags;
203 
204 	if (gpio < 16) {
205 		reg = mpc8xxx_gc->regs + GPIO_ICR;
206 		shift = (15 - gpio) * 2;
207 	} else {
208 		reg = mpc8xxx_gc->regs + GPIO_ICR2;
209 		shift = (15 - (gpio % 16)) * 2;
210 	}
211 
212 	switch (flow_type) {
213 	case IRQ_TYPE_EDGE_FALLING:
214 	case IRQ_TYPE_LEVEL_LOW:
215 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
216 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
217 			| (2 << shift));
218 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
219 		break;
220 
221 	case IRQ_TYPE_EDGE_RISING:
222 	case IRQ_TYPE_LEVEL_HIGH:
223 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
224 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift))
225 			| (1 << shift));
226 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
227 		break;
228 
229 	case IRQ_TYPE_EDGE_BOTH:
230 		raw_spin_lock_irqsave(&mpc8xxx_gc->lock, flags);
231 		gc->write_reg(reg, (gc->read_reg(reg) & ~(3 << shift)));
232 		raw_spin_unlock_irqrestore(&mpc8xxx_gc->lock, flags);
233 		break;
234 
235 	default:
236 		return -EINVAL;
237 	}
238 
239 	return 0;
240 }
241 
242 static struct irq_chip mpc8xxx_irq_chip = {
243 	.name		= "mpc8xxx-gpio",
244 	.irq_unmask	= mpc8xxx_irq_unmask,
245 	.irq_mask	= mpc8xxx_irq_mask,
246 	.irq_ack	= mpc8xxx_irq_ack,
247 	/* this might get overwritten in mpc8xxx_probe() */
248 	.irq_set_type	= mpc8xxx_irq_set_type,
249 };
250 
251 static int mpc8xxx_gpio_irq_map(struct irq_domain *h, unsigned int irq,
252 				irq_hw_number_t hwirq)
253 {
254 	irq_set_chip_data(irq, h->host_data);
255 	irq_set_chip_and_handler(irq, &mpc8xxx_irq_chip, handle_edge_irq);
256 
257 	return 0;
258 }
259 
260 static const struct irq_domain_ops mpc8xxx_gpio_irq_ops = {
261 	.map	= mpc8xxx_gpio_irq_map,
262 	.xlate	= irq_domain_xlate_twocell,
263 };
264 
265 struct mpc8xxx_gpio_devtype {
266 	int (*gpio_dir_out)(struct gpio_chip *, unsigned int, int);
267 	int (*gpio_get)(struct gpio_chip *, unsigned int);
268 	int (*irq_set_type)(struct irq_data *, unsigned int);
269 };
270 
271 static const struct mpc8xxx_gpio_devtype mpc512x_gpio_devtype = {
272 	.gpio_dir_out = mpc5121_gpio_dir_out,
273 	.irq_set_type = mpc512x_irq_set_type,
274 };
275 
276 static const struct mpc8xxx_gpio_devtype mpc5125_gpio_devtype = {
277 	.gpio_dir_out = mpc5125_gpio_dir_out,
278 	.irq_set_type = mpc512x_irq_set_type,
279 };
280 
281 static const struct mpc8xxx_gpio_devtype mpc8572_gpio_devtype = {
282 	.gpio_get = mpc8572_gpio_get,
283 };
284 
285 static const struct mpc8xxx_gpio_devtype mpc8xxx_gpio_devtype_default = {
286 	.irq_set_type = mpc8xxx_irq_set_type,
287 };
288 
289 static const struct of_device_id mpc8xxx_gpio_ids[] = {
290 	{ .compatible = "fsl,mpc8349-gpio", },
291 	{ .compatible = "fsl,mpc8572-gpio", .data = &mpc8572_gpio_devtype, },
292 	{ .compatible = "fsl,mpc8610-gpio", },
293 	{ .compatible = "fsl,mpc5121-gpio", .data = &mpc512x_gpio_devtype, },
294 	{ .compatible = "fsl,mpc5125-gpio", .data = &mpc5125_gpio_devtype, },
295 	{ .compatible = "fsl,pq3-gpio",     },
296 	{ .compatible = "fsl,ls1028a-gpio", },
297 	{ .compatible = "fsl,ls1088a-gpio", },
298 	{ .compatible = "fsl,qoriq-gpio",   },
299 	{}
300 };
301 
302 static int mpc8xxx_probe(struct platform_device *pdev)
303 {
304 	struct device_node *np = pdev->dev.of_node;
305 	struct mpc8xxx_gpio_chip *mpc8xxx_gc;
306 	struct gpio_chip	*gc;
307 	const struct mpc8xxx_gpio_devtype *devtype = NULL;
308 	struct fwnode_handle *fwnode;
309 	int ret;
310 
311 	mpc8xxx_gc = devm_kzalloc(&pdev->dev, sizeof(*mpc8xxx_gc), GFP_KERNEL);
312 	if (!mpc8xxx_gc)
313 		return -ENOMEM;
314 
315 	platform_set_drvdata(pdev, mpc8xxx_gc);
316 
317 	raw_spin_lock_init(&mpc8xxx_gc->lock);
318 
319 	mpc8xxx_gc->regs = devm_platform_ioremap_resource(pdev, 0);
320 	if (IS_ERR(mpc8xxx_gc->regs))
321 		return PTR_ERR(mpc8xxx_gc->regs);
322 
323 	gc = &mpc8xxx_gc->gc;
324 	gc->parent = &pdev->dev;
325 
326 	if (device_property_read_bool(&pdev->dev, "little-endian")) {
327 		ret = bgpio_init(gc, &pdev->dev, 4,
328 				 mpc8xxx_gc->regs + GPIO_DAT,
329 				 NULL, NULL,
330 				 mpc8xxx_gc->regs + GPIO_DIR, NULL,
331 				 BGPIOF_BIG_ENDIAN);
332 		if (ret)
333 			return ret;
334 		dev_dbg(&pdev->dev, "GPIO registers are LITTLE endian\n");
335 	} else {
336 		ret = bgpio_init(gc, &pdev->dev, 4,
337 				 mpc8xxx_gc->regs + GPIO_DAT,
338 				 NULL, NULL,
339 				 mpc8xxx_gc->regs + GPIO_DIR, NULL,
340 				 BGPIOF_BIG_ENDIAN
341 				 | BGPIOF_BIG_ENDIAN_BYTE_ORDER);
342 		if (ret)
343 			return ret;
344 		dev_dbg(&pdev->dev, "GPIO registers are BIG endian\n");
345 	}
346 
347 	mpc8xxx_gc->direction_output = gc->direction_output;
348 
349 	devtype = device_get_match_data(&pdev->dev);
350 	if (!devtype)
351 		devtype = &mpc8xxx_gpio_devtype_default;
352 
353 	/*
354 	 * It's assumed that only a single type of gpio controller is available
355 	 * on the current machine, so overwriting global data is fine.
356 	 */
357 	if (devtype->irq_set_type)
358 		mpc8xxx_irq_chip.irq_set_type = devtype->irq_set_type;
359 
360 	if (devtype->gpio_dir_out)
361 		gc->direction_output = devtype->gpio_dir_out;
362 	if (devtype->gpio_get)
363 		gc->get = devtype->gpio_get;
364 
365 	gc->to_irq = mpc8xxx_gpio_to_irq;
366 
367 	/*
368 	 * The GPIO Input Buffer Enable register(GPIO_IBE) is used to control
369 	 * the input enable of each individual GPIO port.  When an individual
370 	 * GPIO port’s direction is set to input (GPIO_GPDIR[DRn=0]), the
371 	 * associated input enable must be set (GPIOxGPIE[IEn]=1) to propagate
372 	 * the port value to the GPIO Data Register.
373 	 */
374 	fwnode = dev_fwnode(&pdev->dev);
375 	if (of_device_is_compatible(np, "fsl,qoriq-gpio") ||
376 	    of_device_is_compatible(np, "fsl,ls1028a-gpio") ||
377 	    of_device_is_compatible(np, "fsl,ls1088a-gpio") ||
378 	    is_acpi_node(fwnode))
379 		gc->write_reg(mpc8xxx_gc->regs + GPIO_IBE, 0xffffffff);
380 
381 	ret = devm_gpiochip_add_data(&pdev->dev, gc, mpc8xxx_gc);
382 	if (ret) {
383 		dev_err(&pdev->dev,
384 			"GPIO chip registration failed with status %d\n", ret);
385 		return ret;
386 	}
387 
388 	mpc8xxx_gc->irqn = platform_get_irq(pdev, 0);
389 	if (mpc8xxx_gc->irqn < 0)
390 		return mpc8xxx_gc->irqn;
391 
392 	mpc8xxx_gc->irq = irq_domain_create_linear(fwnode,
393 						   MPC8XXX_GPIO_PINS,
394 						   &mpc8xxx_gpio_irq_ops,
395 						   mpc8xxx_gc);
396 
397 	if (!mpc8xxx_gc->irq)
398 		return 0;
399 
400 	/* ack and mask all irqs */
401 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IER, 0xffffffff);
402 	gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR, 0);
403 
404 	ret = devm_request_irq(&pdev->dev, mpc8xxx_gc->irqn,
405 			       mpc8xxx_gpio_irq_cascade,
406 			       IRQF_NO_THREAD | IRQF_SHARED, "gpio-cascade",
407 			       mpc8xxx_gc);
408 	if (ret) {
409 		dev_err(&pdev->dev,
410 			"failed to devm_request_irq(%d), ret = %d\n",
411 			mpc8xxx_gc->irqn, ret);
412 		goto err;
413 	}
414 
415 	return 0;
416 err:
417 	irq_domain_remove(mpc8xxx_gc->irq);
418 	return ret;
419 }
420 
421 static int mpc8xxx_remove(struct platform_device *pdev)
422 {
423 	struct mpc8xxx_gpio_chip *mpc8xxx_gc = platform_get_drvdata(pdev);
424 
425 	if (mpc8xxx_gc->irq) {
426 		irq_set_chained_handler_and_data(mpc8xxx_gc->irqn, NULL, NULL);
427 		irq_domain_remove(mpc8xxx_gc->irq);
428 	}
429 
430 	return 0;
431 }
432 
433 #ifdef CONFIG_ACPI
434 static const struct acpi_device_id gpio_acpi_ids[] = {
435 	{"NXP0031",},
436 	{ }
437 };
438 MODULE_DEVICE_TABLE(acpi, gpio_acpi_ids);
439 #endif
440 
441 static struct platform_driver mpc8xxx_plat_driver = {
442 	.probe		= mpc8xxx_probe,
443 	.remove		= mpc8xxx_remove,
444 	.driver		= {
445 		.name = "gpio-mpc8xxx",
446 		.of_match_table	= mpc8xxx_gpio_ids,
447 		.acpi_match_table = ACPI_PTR(gpio_acpi_ids),
448 	},
449 };
450 
451 static int __init mpc8xxx_init(void)
452 {
453 	return platform_driver_register(&mpc8xxx_plat_driver);
454 }
455 
456 arch_initcall(mpc8xxx_init);
457